Photographic emulsions



United States Patent M PHOTOGRAPHIC EMULSIONS Thomas David Smith, RedBank, N. J., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation ofDelaware .No Drawing. Filed May 1, 1957, Ser. No. 656,195

11 Claims. (Cl. 96-107) This invention relates to photographic silver halide emulsions containing a non-optical sensitizing agent havng at least one polyoxyalkylene group. More particularly 1t relates to such emulsions containing a hydrocarbonsubstituted mononuclear monohydric phenol of at least l carbon atoms wherein a hydrocarbon substituent is in )the para-position to the hydroxyl group. The invention 2,955,037 Patented Oct. 4, 1960 ance with the invention, in addition to the hydrocarbon substituent in the para-position to the hydroxyl group, may contain one, two or three additional hydrocarbon substituents in the benzene ring containing the phenolic hydroxyl group. Among the hydrocarbon substituents which may be present inthe para-position and in the other also relates to photographic elements hearing at least one layer of such an emulsion.

It is known that photographic silver halide emulsions which have been sensitized to very high levels tend to produce fog on development. This photographic fog is due to the existence in the emulsion of silver halide grains which are developable without exposure to light. In addition, fog may be produced in photographic emulsions durmg storage, particularly under adverse conditions of temperature and humidity.

As is well known, the sensitivity of photographicemulsions can be increased in a number of ways. -One of these is by adding derivatives of alkylene oxides, such'as' polyalkylene oxides or condensation products of alkylene oxides or polyalkylene oxides, e.g., ethylene oxide, with acids, alcohols or amines as disclosed in U.S. patents Blake et al. 2,400,532, Blake 2,423,549, Blake 2,441,389 and Carroll et al. 2,716,062. However, these compounds tend to cause fog when photographic materials, the emulsions of which contain them, are stored for any length of time. Attempts to reduce this fog have involved the use of antifogging agents which are frequently detrimental to certain photographic properties. In particular, certain such agents tend to reduce the photographic speed of film when exposed to relatively low intensity illumination.

It is therefore an object of this invention to provide means for reducing fog in photographic emulsions. Another object is to reduce fog produced on storage of emulsions, particularly in tropical climates or under other adverse conditions of temperature and humidity. A further object of this invention is to provide silver halide emulsions sensitized with alkylene oxide polymers and of improved stability and less tendency to form an objectionable amount of fog on normal storage and photographic positions of the benezene ring are alkyl radicals of 1 to 18 carbon atoms, e.g., methyl, ethyl, n-propyl, isopropyl, tbutyl, sec-amyl, t-amyl, t-octyl, n-nonyl and ndodecyl; aryl, e.g., phenyl, naphthyl and bi-phenyl; aralkyl, e.g., benzyl, a-cumyl and naphthylmethyl, and cycloalkyl, e.g., cyclopentyl and cyclohexyl. In an important specific em-' bodiment of the invention, the. hydrocarbon substituted mononuclear monohydric phenols have at least one t-butyl substituent in the molecule.

It has been found that when 5 to 50 millimoles of a hydrocarbon-substituted mononuclear monohydn'c phenol described above is added per mole of silver halide to the sensitized emulsions that the speed (i.e., response of the emulsion to radiation of both high and low intensity), contrast and fog values of the resulting emulsions remain substantially at the initial values of the emulsion, even when the emulsions or emulsion layers are maintained under adverse storage conditions for short or extended periods of time, e.g., at an elevated temperature and/or high conditions of humidity.

The invention is not limited to any particular type of light-sensitive silver halide as it is useful with silver chloride, silver bromide, silver iodobromide, silver chlorobromide, etc, emulsions and mixed emulsions of these 7 types. It is particularly efiicacious in silver iodobromide emulsions containing about 2 mole percent iodide and the rest bromide. These emulsions may be sensitized by meansof non-opticalor chemical sensitizing agents other than the polyoxyalkylene polymers mentioned above. Thus, noble metal sensitizers, e.g., gold compounds, e.g.,- chlorauric acid and auric trichloride, may be present in association with sulfur sensitizers containing labile sulfur, e.g., sodium thiosulfate, allylthiocarbamide, alkali metal thiocyanates, sodium sulfide, and allylthiourea. These sensitizers are generally used in amounts of 0.005% or less based on the weight of the silver halide. Moreover, the silver halide emulsions may contain one or more optical sensitizing agents, e.g., cyanine, carbocyanine, merocyanine pseudocyanine, cyazine, etc., dyes.

With regard to the non-optical sensitizers which contain at least one polyoxyalkylene group,-there are a relatively large number of such compounds known to the art, suitable compounds being described in the above-identified patents. These compounds include not only the polyalkylene oxides or glycols wherein the oxyalkylene groups contain 2 to 4 carbon atoms but also the condensation elements embodying such emulsions. Still other objects 7 monohydric phenol of at least 9 carbon atoms with a photographic silver halide emulsion containing sensitizing amounts of a non-optical or chemical emulsion sensitizing agent having a molecular weight of at least 282 and containing at least two and preferably at least six oxyalkylene units of 2 to 4 carbon atoms. The mononuclear monohydnic phenolsused in accord products of alkylene oxides of 2 to 4 carbon atoms with glycols, fatty acids, saturated aliphatic amines, and hexitol ring dehydration products, said compounds having a molecular weight of at least 282, suitable specific com pounds of which are disclosedin the aforesaid patents. In general these sensitizing compounds are present in amounts from 0.1 to 2.0 g. per mole of silver halide. While gelatin is the preferred binding agent for the silver halide grains, other water-permeable amphotem'c protein protective colloids, e.g., albumin and casein, can be used. Also, agar-agar, alginic acid and the alginates, polyglycuronic acid, polyvinyl alcohol, polyvinyl acetals including those containing color forming nuclei, and other natural or synthetic water permeable colloids useful in making photographic emulsions can be used as the original colloid during the precipitation, or in the final emulsion as bulking agents.

,Thehydrocarbon-substituted mononuclear monohydric phenols are preferably added to the silver halide emulsion after'it has been brought to its maximum sensitivity.

and the conventional adjuvants are added just prior to coating onto a suitable support to form a photographic element. They can, of course, be added at an earlier stage, that is, at the time of second digestion.

The invention will now be further illustrated by, but is not intended to be limited to, the following examples wherein the silver halide weight ratio, unless otherwise indicated, is 1.6 mole percent iodide and the remainder bromide.

Example 1 A high speed gelatino-silver iodobromide, emulsion was, digested with an organic sulfur compound and gold chloride. After digestion the emulsion was divided into three portions. One portion was treated with 0.5' gram of a condensation product of polyethylene oxide with oleyl alcohol having a molecular weight of approximately 900 (Emulphor ON-870 manufactured by the Antara Chemicals Division, General Aniline and Film Corp.) per mole of silver halide. To a second portion was added 0.5 gram of said condensation product together with 20 millimoles of 2-benzyl-4-methyl-6-t-butylphenol, which is disclosed and claimed in assignees Pickl and Stevenson US. application Ser. No. 494,262 filed Mar. 14, 1955, per mole of silver halide. A third portion having neither of these additions was used as a control. The emulsions were coated on cellulose acetate film base and were exposed to X-rays in the presence of an intensifying screen at two different intensity levels. The exposure of greater intensity has been designated as No. 2 and that of lower intensity and longer time as No. 1.

The coatings'were developed for 5 minutes in a developer of the following composition:

grams Metol V 3 Anhydrous sodium sulfite 50 Hydroquinone 9 Anhydrous potassium carbonate 50 Potassium bromide 4.5

Water to make 1000 ml.

is given in terms of a reciprocal of exposure at a density of 0.7. If fog is greater than 0.40 the speed and gamma numbers are of no significance and are therefore not included in such cases.

FRE SH RESULTS No. 2 Exposure No. 1 Exposure Compound Amount Fog per Mole Speed Gamma Speed Gamma Control None 940 2. 67 450 2. 43 .15 Polyoxyethy- 0.5 g 1, 040 3.02 520 2. 52 30 oleyl alcohol (I). Iplus 0.5g f 93% 1,010 2. 43 510 2. 19. .16

butyi phenol.

2 MONTHS vROOM AGING N0. 2 Exposure No. 1 Exposure Compound Fog- Speed. Gamma Speed Gamma IControl; 640 2. 45 320 2. 00 .23 .46 Iplus phenolic compound 670 2.45 340 1.97 .22

ONE WEEK AT 120 F. AND 65% R.H.

Compound Fog Control .24 I .78 I plus phenolic compound 18 Example 2 A. gelatinorsilver iodQbromideemuIs-ion, digested with sulfur and gold compounds, wasdivided into three portions. one po t o was. t ated. with .67 g. qfp ye y ene oxide monostearate having an average molecular weight of from 9.5;Q-.=105;0,'('Carbowax 1000 monostearate manufactured by the ,Glyco Products Company) per mole of silver halide. To a second portion there was added, .67 g. of the polyethylene oxide monostearate per mole of silver. halide together with 5:0 millimoles of 2- benzyl-4 methyl-6-t-butylphenol' (11) per mole of silver halide. Neither of these additions were made to a third portion, which was used as a control, I

' Coating, exposure and" development were carried out as in Example 1. Agingtests for 2 months under normal room conditions were carried out with the following results.

FRESHRESULTS 30 i No. 2 Exposure No. 1 Exposure .Q m quns Am t Fog per Mole Speed Gamma Speed Gamma Control 'Nouem 850 2. 2 v 420 2.13 .13 IPolyethylene .67 1,000 2. 46- 440. 2. 22.3 .16;

oxide monostearate. Iplus. .67 11--.-.. fiomilli- 960 1 2.68- 440 2.5 5 .14

moles 2 oNrrHs ROOM AGING No. 2*Exposure N0. 1 Exposure Compound I g 7 I og.

' Speed Gamma Speed Gamma Gdutrol- 600 2. 03 320 1.76 .20 I 70e- 2.3 1 330 1;.76 .28 32 0 2-32. 38.0. .9.5. .2

Example 3 ethylene oxidetogether with'16.7 millimoles of 2-benzyl- 4-me'thyl56-t-butylphenol (11;) per mole-of silver halide. Neither offthese additions ,wasmade to a third portion of the emulsion. p p p Coating, exposure, development and aging were carried out. as. n Ex p 1 FRESH! RESULTS No.2Exposure NmlExposure- Qpmpo nd. Amount Fog I Speed Gamma.Speed Gamma Control" None 950 s. 11 460 2:72 .18 1?plyeth-yleme .67 1,170 3.08 530 2. 70 .24 Ioiride (I). 67

nus v 1,o10 are 529 2.89 .22

2 MONTHS nooM AGING FRESH RESULTS No.2 Exposure No. 1 Exposure No. 2 Exposure No. 1 Exposure Compound Fog Compound Am o i m t Fog per e Speed Gamma Speed Gamma 5 Speed Gamma Speed Gamma Control 660' 2.139 390 2.15 .3% Control None---" 720 2.38 390 2.04 .20 r v .55 IplusII. 960' aoo 460 2.34 .25

W p 726 2.77 390 2.48 .23 ONE WEEK AT 120 E. AND 65% R.H.

Compound Fog ONE MONTH ROOM AGING .40 V No. 2 Exposure No. 1 Exposure 3.20 Compound H Fog II. .48

. Speed Gamma Speed. Gamma The Carbowax 6000 referred to above is manufac- 1 c tured by the Carbide and Carbon Chemicals Company. 640 1 92 330 1 52 I g IpluslI 680 2.46 390 2.17 .22 Example 4 ,A gelatino-silver iodobromide emulsion, digested with ONE'WEEK 1 AND 65% sulfur and gold compounds, was divided into three portions. One portion was treated with .53 g. of the polyethylene oxide described in Example 3 per mole of silver halide. To a second portion were added .53 g. of th gontml .3g polyethylene oxide and 20 millimoles 2,3,6-t-butyl-4- I' lus II- .28 phenylphenol (II) per mole of silver halide. The preparation of this phenol will be found in J. Chem. Ed. 32, Example 6 312 (1955). Neither of these additions was made to a A-gelatlno-srlver iodobromide emulsion, dlgested with third portion of the emulsion.

:ICoating, exposure,'development and aging were carried out as in Example 1 except that the emulsions were tested after one month of room temperature aging.

FRESH RESULTS N o. 2 Exposure No. 1 Exposure Amount Fog 'per Mole Compound h Speed Gamma Speed Gamma None 2. 13

20 milli- ONE MONTHBOOM AGING Contr l 350 I Polyethylene at be 0 (71KB moles.

No. 2 Exposure No. 1 Exposure Compound Fog Speed Gamma Speed Gamma Control. I plus II ONE WEEK AT 120F. AND 65% R.H.

Compound 2 Contr I plus II- I Example 5 A gelatino-silver bromoiodide emulsion, digested with sulfur and gold compounds, was divided into three portions. One portion was treated with .53 g. of the polyethylene oxide described in Example 3 (Carbowax sulfur and gold compounds, was divided into three por- -tions. One portion was treated with .5 3 g. of a polyethyl- 6000) per mole of silver halide. To a second portion was added .53 g. of the polyethylene oxide and 20 millimoles p-n-nonylphenol (II). per moleof silver halide. .Neither of these additions were made to a third portion of the emulsion.

'Coating, exposure, development and aging were carried 4 FRESH RESULTS and aging were car- No. 2 Exposure No. 1 Exposure Compound Amount Fog per Mole Speed Gamma Speed Gamma Control 720 2. as 390 2. 04 .20 Polyethylene 65 oxide (I).

ONE MONTH ROOM AGING N o. 2 Exposure No.1 Exposure Compound Fog Speed Gamma Speed Gamma TControl 640 1.92 330 1.52 .1!i

. 7 I plus II 720 2. 43 370 1. .20

.ON E WEEK AT F. AND 65% R.H.

Compound Fog Control .26 I 1.95 I plusII- .85

Example 7 I A gelatino-silver iodobromide emulsion, digested with sulfur and gold compounds, 'was divided into three poitions. One portion was treated with .53 g. of the polyethylene oxidedescribed in Example 3 (-Carbowax) per wanna?! 7 mole of silver halide. To a second portion was added .53 vg. of thepolyethylene. oxide together with 20 millimoksp-n-dodecylphenol (II) per mole Of silver halide. Neitherof theseadditionswasmade to a third spontion ExampleQ A gelatinosilver iodobromide emulsion, digested with sulfur and :goldcornpounds, was divided into three portions. One portion was treated with .27 g. bfthe polygz i zf develo meat and were ar ethylene oxidedescribed in Example 3 (Carbowax fl out g P agmg" 6000) per mole of silver halide. To a' second portion 1. p was added 0.27 g. of-the polyethylene oxide and amix- FRESH RESULTS tu're .(II) of 8 millimoles of Z-bepzyl-4-nmthyl-6-t-butyl- I I 10 phenol. and .2 millimoles fof 2,3,6-tri t-butyl 4-phenylphe d A No.2Exposure N0.1Exposure l 1101 per mole of silver halide. 9 m? fgk g l Coating, exposure, development and aging werecam'ed =Speed Gamma speed Ga outas to Example 4.

' FRESH RESULTS Control 720 2. 38 390 2. 04 20 Polyethylene ,53; I I I I I oxide (I). v N0. 2 Exposure No. 1 Exposure; I plus .53 z Compound Amount Fog II milll- 7 3.16 390 2.49 .23 per Mole 1 moles. I I speed Gamma Sp ee d Gamma ONE MON'IH no'onilgeme. 20 emlalELQELH. 1,030 2. 70 420 2. 48 .28 Polyethylene 1,080 3.08 480 2. 4s 32 oxide (I).

.No.2Exposure No.1Exposure Compound Fog 1; 048 3.06 460 2.47 .18

Speed Gamma Speed Gamma 25 ONE MONTHTROOM AGING Control- .640 1.92 ,330 1.52 I I I I I I plus'H 670 2.51 830 V 2.37. 2'20 No.2Exposure No.lExposure Compound I v 395 ONE WEEK AT 120 F. AND 65% R.H. Speed Gamma Speed; Gamma Compound .Fog pontrol 340 an 370 1. e9 Y i plus-II .3 880 2 2.73 .400' 2. 211 :38 Control 26 p I I I L95 I I I.. V 3 35 ONE WEEK AT 120 F. AND 65% RH.

Example Compound Fog- A 'gelatill'o-silv'er 'iodobromide emulsion, digested with c i V ontrnl 0.56 sulfur and gold compounds, was dlvlded into three porr 2.12 tions. One portion was treated with .53 g. ofthe con- [Plusn- I densation product Of'EXflIHPlC 1 (Emulphol ON-870) per mole of silver halide. To a second portion was :Example 10 added .53 g. of the above condensation product together with s millimoles of t-octylphenol A E k i wd m i m l mg 'dl e i W11 sulfur and gold compounds, was dlvlded mto three por- 5 'tions. One-portion was treated with 1.1 g. polyoxyethy-l- H-QOC GHZ-C-CHX ated oleyl alcoh'ol'of Example 1 per mole of silver halide.

(i311; To a second portion was added 1.1 'gJofthe above con i v densat'i'onproduct per mole of silver halide together with per mole of silver hallde. Nelther of .these addltlons was 20 minimqles f p-t-butylphenol (II). .made to a third portion of the emulsion which served as I vCoIImingIII exposureI develppment and aging were carried a ffl' out as in Example 1. 4 7

Coating, exposure, development and ag ng were carried I 7 out as in Example 1' and the fresh results andone week FRESH RESU TS at 120 F. and 65% RH. are as follows: FRESH RESULTS No.2 Exposure No.1 Exposure Compound Amo ltlnlt Fog Perl 0 6 No- 2 1 Speed Gamma Speed Gamma Amount Exposure Exposure Compound per Mole Fog I V V Q tynl Nana 720 2. 27 440 2. 01 i :33 Speed Gamma Speed Gamma 33o1yomthy1 .I I .82

. ated oleyl Contr l N n 980 2489 .24 2 3: 016) m Poly0xyethy1- .53 1,140 3.02 .460 2.46 33 [I 0 mm. 0 2, 3 450 .19 40 ated oleyl moles 2 alcohol (I) .65 lplus .53g V 2 II 5 fig ONE MONTH ROOM AGING V ONLE AT 12 10 1. AND I t. H. No.2Exposure No.-1Exposure Compound I Fog Compound Fog Speed Gamma Speed Gamma "65M? h I i I I x i .24 ooimshj :56 .34 T .1 plus in. .21 I plusllfl. 750 an 470 2.19 .38

..\ ,d 2 )I m 616$ WEEK AT 120 F. Quip 65% an. ONE MONTH ROOM AGING Oompwnd I No. 2 Exposure No. 1 Exposure Compound Fog Speed Gamma Speed Gamma Control.. .56 I .74 Example I plus 11 800 2.47 490 2. 11 .36 A gelatino-silver iodobromide emulsion, digested with sulfur and gold compounds, was divided into three por- 1 ONE WEEK AT AND 65% tions. One portion was treated with .5 g. of the poly: oxyethylated oleyl alcohol of Example 1 per mole of Com ound F silver halide. T o a second portion was added .5 g. of the p 0g above condensation product per mole of silver halide to- 15 Comm] 48 gether with millimoles of p-benzylphenol (II). I 1: 18 Coating, exposure, development and aging were carried I 91115 H out as in Example 4.

FRESH RESULTS 2o Example 13 a NozExPosme lExposure A gelatlno-sllver lodobromlde emulsion dlgested with Compound Amount Fog sulfur and gold compounds, was dlvlded into three por- D Mole tions One portion was treated with 1 l g of the cons d G s 1 G mm pee mm a a dCIISatIOH'PI'OdHOt of Example 1 per mole of silver halide. To a second portion was added 1.1 got the condensation 0 tr 1 N 720 2.27 320 2.01 .38 P l ro yethyl- .5?! .72 product per mole of sllver hallde together wlth 20 millimoles of 2,4-di-sec-amylphenol (H). 1 plus 5 g 840 Coating, exposure, development and aging were carried 11 'zomllll- 2.49 340 2.15 .26 m out as in Example 4.

FRESH RESULTS ONE MONTH ROOM AGING No. 2 Exposure No. 1 Exposure No. 2 Exposure No. 1 Exposure Compound i gggg mg compound Fog Speed Gamma Speed Gamma Speed Gamma Speed Gamma ggntlfirol 1N fne. 690 2. 54 480 2. 19 Control 540 1.81 430 1.87 .56 I 620 2.27 430 2.02 .74 3233f 1 plus II 750 2.06 470 2. 26 .33 I mus; H g

II 20 milli- 760 3. 17 490 2. 49 32 moles ONE WEEK AT 120 F. AND 65% R.H.

ONE MONTH ROOM AGING Compound Fog Contr No. 2 Exposure No. 1 Exposure 1 1. 18 Compound 8 I plus II- 38 50 Speed Gamma Speed Gamma E 1 12 Control 670 2. 25 400 1. 9s 2s r. I. 228 as 2-22 2% r us A gelatlno-sllver lodobromide emulsion, digested with sulfur andgold compounds was divided into three portions. One portion was treated with 0.5 g. of the poly- ONE WEEK AT 120 F. AND RH. oxyethylated oleyl alcohol of Example 1 per mole of silver halide. To a second portion was added 0.5 g. (Emulphor ON) per mole of silver halide together with 10 millimoles of p-t-amylphenol (II).

Coating, exposure, development and aging werecarried out as in Example 4.

FRESH RESULTS v (65 Example 14 Compo Amount zExposum No.1 Exposure Fo A gelatino-silver iodobromide emulsion, digested with per Mme speed Gamma Speed Gamma sulfur and gold compounds, was divided into three portions. One portion was treated with 0.5 g. of the con- Control None 720 2.27 .400 2.01 .38 ,7 densation product of Example 1 per mole of silver halide. 1 ggigh oleyl To a second portion was added 0.5 g. of the above conj alcohol. densation product per mole of silver halide together with 950 2.73 510 2.19 A0 20 millimoles of p-n-butylphenol (II). moles. Coating, exposure, development and aging were c rried .175 outasinExample4. I; 1

manor-03v FRESH RESULTS No.2 Exposure N 1 Exposure Compound Amount 7 Fog per Mole Speed Gamma Speed Gamma Control None 720 2.40 420 2.13, v .25 Polyoxyethylated 0.5 .50 I oleyl alcohol (I). 0

us g II? 20ml1li- 960 2.55 I 430 2.22 .26

moles ONE MONTH ROOM AGING N0. 2 Exposure No. 1 Exposure I Compound Fog Speed Gamma Speed Gamma Control 690 2. 18 350 1. 83 it: I Iplus II 940 "2.58 430 2.06 .15

Example '15 A gelatino-silver iodobromide emulsion, digested with sulfur and gold compounds, was divided into three portions. One portion was treated with 0.5 g. of the condensationproduct of Example 1 per mole of silver halide. To a second portion was added 0.5 g. of the above condensation product per mole of silver halide together with 20 millimoles of p-isobutylphenol (II).

Coating, exposure, development and aging were carried out as in Example 1.

FRESH RESULTS No. 2 Exposure No. 1 Exposure 7 Compound Amount Fog per Mole Speed Gamma Speed Gamma Control None 720 2. to 420 2.1a Polyoxyethylated 0.5g

oleyl alcohol (I). Iplus 0.5 g-

20 mllll- 970 2.71 440 2.23

moles.

ONE MONTH' ROOM AGING No.2 Exposure No. 1 Exposure Compound Fog Speed Gamma Speed Gamma Control 690 2.18 350 1. 83 i fplusllm- .I 880 2. so 420 2.11 I22 ONE WEEK AT.120 F. AND. 65% RH.

Compound Fog Contr l .34 I .96 Lplus II- 48 Example 16 A gelatino-silver iodobromide emulsion, digested with sulfur and gold compounds, was divided'into-three portions. One portion was treated with 0.5 g. of the condensation product of Example 1 per mole of silver halide. To a second portion there was added 0.5 g. of the above condensation product-together with 20 millimoles of 2,6- .di-t-butyl-4-methylphenol (II). Neither of these additions was made to a third portion.

Coating, exposure, development and agingwere carried out as in Example 1. J

.ONE WEEK AT F. AND 65% RH.

Compound Example 17 A gelatino silver iodobromide emulsion, digested with sulfur and gold compounds, was divided into three por- I FRESH RESULTS 7 No. 2 Exposure No. 1 Exposure Compound Amount Fog per Mole Speed Gamma Speed Gamma ONE MONTH ROOM AGING No; 2'Exposure No. 1 Exposure Compound Fog Speed Gamma. Speed Gamma IControl 640 2.29 330 1. 83 .22 .63 I plus II 610 3. 49 290 2. 37 .24

ONE WEEK Arum-F. AND 65% an.

Compound Fog Control .20 I 1.92 I plus IL. .24

Example 18 'A gelatino-silver iodobromide emulsion, digested with sulfur and gold compounds, was divided into three portions. One portion was treated with 0.5 g. of the polyethylene oxide'of Example 3 (I) per mole of silver halide. To a second portion was added 0.5 g. of (I) together with 20 millimoles of p-alpha-cumylphenol (II). Neither of these additions was made to a thirdportion.

Coating, exposure, processing and aging were carried out as in Example 1. r

i3 14 FRESH RESULTS 696 exposure, p c s and aging Wef out as in Example 1.

No. 2 Exposure No. 1 Exposure FRESH RES UI J'i Compound Amlolmit Fog e 0 6 l p r Speed Gamma Speed Gamma 5 ,I No.2 Expos'ui-e No.1 Exposure Oompound Amloiimlt Y Fog Control None 860 2.70 300 2.34 .15 per 06 Speed Gamma Speed Gamma g 810 2.71 400 2.46 .14 Control New 10 I- 0.52 .58

Iplus 0.5 I 20mi11i- 780 2.81 420 2.35., .40 ONE MONTH ROOM AGING moles. I Y

No.2 Exposure No. 1 Exposure TWO MONTHS AGING Compound Fog Speed Gamma Speed Gamma No.2Exposure No.1Exposure Compound Fog;

gontrol 700 2.19 320 2.11 Speed Gamma Speed Gamma IplusII 720 2. 53 330 2.49 I12 Control .461 I 740 3.29 330 2.49 .38: ONE WEEK AT 120 F. AND 05% R.H. Iplus II 720 2.37 400 2.29. .33:

C m d F o palm 0g The 2-sec-butyl-4-ethylphenol was prepared by the. Comm .22 Clemmenson reduction of 2-sec-butyl-4-hydroxyacetophe-- T- 1.98 none. The latter ketone was prepared by the Friedel land U Crafts acylation of o-sec-butylphenol with acetyl chloride.- in the presence of aluminum chloride by the generall Example 19 procedure of Rosenmund and Schulz. Arch. Pharmaz; A gelatino-silver iodobromide emulsion containing 6.8 deut- P 308 (1927)- The ketone was; mole percent iodide and optically sensitized with a mixreduced by the general meflwd of CImmQDSOn [Barf ture of two carbocyanine dyes was divided into three 53 (1 914)] i a Pomon f resulting f l portions. One portion was treated with 0.3 g., per mole y redlstlued to oglve colorless hquld havmg a bmlmg? of silver halide, of a polyethylene oxide (I)' having an P0111t of 136-138 /18 average molecular Weight of 3000-3700 (Carbowax E l 21 4000 made by Carbide and Carbon Chemicals Comxamp e I pany). To a second portion there was added 0.3 g. of the polyethylene oxide compound together with 5.3 g. 2 ethy14 lsqiropylphenol was Prepared by the Clem f ixture (H) of henols described in Exam 1e 9 menson reduction of Z-aCGtYI-i'ISOPI'OPYIPhCIIOI by the g d ortion was added 03 U of procedure described in Ber. 47, 53 (1914). The ketone 16 of halide andelo 6 of p was Prepared by the acylation of p-isopropylphenol with i ulsion was ex osed to a acetyl chloride in the presence of AlCl by the general procedure of Sandulesco & Gerard, Bull. Soc. Chim. [4] white h ght and to a red hght and processed in the con- 47 1300 (1930) Yt g z zg ig g ss g tenns of a A gelatino-silver iodobromide emulsion, digested with Ell-Drop xp y 4.5 sulfur and gold compounds, was divided into three por- FRESH RESULTS tions. One portion was treated with 0.5 g., per mole of T L h silver halide, of the condensation product described in Amwnt White ig t B Example 1 (I) To a second portion there was added F Fl W la le 0g 0.5 g. of (I) together with 20 millimoles of 2-ethyl-4- Speed Gamma 5.0 isopropylphenol (II). Neither of these additions was made to a third portion. Coating, exposure, processing and aging was carried 0.3 480 1.00 .12 4.0 d E 1 1 2:; 0 .11 M out as descnbe 1n xampe 480 .91 .09 3.7 FRESH RESULTS ONE WEEK AT 4 AND RH; No. 2Exposure No. 1 Exposure Compound Amglallit Fog Compound Amount Fog per 06 Speed Gamma Speed Gamma 9. Control N one 45 r v 0.3 .09 0, .58. 1131115 -3 08 Inlns 0.52 i lus 20mi11i- 860 3.08 430 2.54 .24. 1036 08 moles- 65. Example 20 TWO MONTHS AGING A gelatino-silver iodobromide emulsion, digested with NO 2Ex osure No IEX owe sulfur and gold compounds, was divided into three por- Compound p p Fog v tions. One portion was treated with 0.5 g. per mole of silver halide of the condensation product described in Speed Gamma Speed Gamma Example 1 (Emulphor ON) (I). To a second portion Control was added 0.5 g.of (I) together with 20 millimoles 0f r j 740 3.20 330 2.40 I 38 2-sec-buty1-4-ethylphenol (II). Neither of these addi- IPlusH 720 x1 =33: tions was made to a third portion.

Example 22 A gelatino-silver iodobromide emulsion, digested with sulfur and gold sensitizing compounds, was divided into three portions. One portion was treated with 0.5 g., per mole" of silver halide, of the polyethylene oxide compound (I)' of Example 1. To a second portion there was added 045' g. of (I) and millimol-es of a 2-methyl-4; ethylphenol (II) per mole of silver halide. Neither of these i s. was add d t a third p n-V Coating, exposure, processingand aging were carried out as'in- Example T.

FRESH RESULTS No.2 Exposure N o. 1 Exposure Compound Amount Fog per'Mole Speed Gamma Speed Gamma Contr Nona 0.5 a .58 Iplus 0.5g

I .20 mtllr 850 3. 67 400 2.99 .38 moles TWO MONTHS AGING No. 2 Exposure No. lExposure Compound 1 Fog Speed Gamma .Speed Gamma I Qontrol .Q. 46 L 740 3. 29 230 2. 49 .33 I-plus II 760 3. 4:1 360 2.76 .23

Example 23 A gelatino-silver iodobromide emulsion, digested with halide. Neither of these additions was made to a third portion-which served as a control; Coating; exposure and development were carried out as in Example 'lfwith the following results: 1

FRESH RESULTS No. 2 Exposure No. 1 Exposure Compound Amount V Fog .per'Mole' Speed Qamma Speed Gamma Control None 880 2.39 430 2.01 v .27 0.67'2 .59 Iplus 0.67g .1 l0 milll- 1,030 2. 455 2.30 .36

moles v ONE MONTH ROOM AGING N o; 2 Exposure Compound Fog Speed Gamma ONE WEEK AT 120? F. AND RH.

Compound Fog Control .48

1.60 I plus II .66

The 2-n-octyl-4,S-dimethylphenOl (B'.P.l38 C./l m111.; (n-) 1.5060) was prepared by' the Clemmensen reduction of '2-'n-octanoyl-4;S-dimethylphenol. The ketone 16 was obtained from the Friedel crafts acylation of 3,4- dimethylphenol with n-octanoyl chloride in the presence of aluminumchloride.

In place of the specific hydrocarbon-substituted mononuclear monohydric phenols usedin the foregoing examples there may be substituted one or more other such compounds falling within the generic characterization given above. Suitable additional compounds include 4-tbuty1-3-methylphenol, 2-1x-methyl-benzyl-4-t-butylphenol, p-phenylphenol, p-sec.-butylphenol, and 2-t-butyl-4-methylphenol. These compounds aregenerally added after digestion and after addition of the polyoxyalkylene sensitizing compound. At the same time other compounds having antifogging properties can be added to the emulsionsQ Suitable antifogging agents which can be used include benZotriazole, nitrobenzirnidazole, l-phenyl-5- mercaptotetrazole, and benzothiazole.

The resulting photographic emulsions can be coated onto any suitable support to make the desired type of photographic element. Suitable supports include cellulose esters, e.g., cellulose'acetate, cellulose nitrate, cellulose acetate butyrate, cellulose propionate; super polymers; e.g., nylon, polyethylene terephthalate, polyvinyl chloride, vinylidene chloride copolymers wi h vinyl acetate, acrylonitrile, etc; metal sheets or foils, e.g., aluminum and zinc; and paper including resin-coated and bary ta coated paper; as well as glass plates, inter alia.

An advantage of the invention is that it provides photographic emulsions and elements with improved stability and aging characteristics. 7 t enables one to obtain the useful sensitizing action of the polyoxyall'cylene compounds without an undue degree of fog being formed upon storage of thephotographic elements for long periods. 1 I Another advantage is that the improved emulsions and emulsion layers can be made by the addition ofreadily' available chemical compounds. A further advantage is that the improved emulsions do not require the use of expensive chemicals or tedious procedures. A still further advantage is that thetspeed of the aforedescribed silver halide emulsionsto light of various intensities is not'afiected to the same degree as known non-phenolic antifogging agents. A related advantage is that while the hydrocarbon-substituted mononuclear monohydric phenols have an antifogging action in photographic silver halide emulsions sensitized with polyoxyalkylene compounds, they dolnot have a significant effect on other photographic properties, e.g., contrast, graininess, resolution, optical sensitization and latent image stability.

I claim:

l. A photographic, water-permeable colloid-silver halide emulsion containing per mole of silver halide (1) from 0.1 to 2.0 grams of a non-optical sensitizing agent having a molecular weight of at least 282 and containing at least 2 oxyalkylene units of 2 to 4 carbon atoms and being taken from the group consisting of polyalkylene ether glycols, and condensation products of alkylene ox ides of 2 to 4 carbon atoms with monohydric alcohols, glycols, fatty acids, saturated aliphatic amines, and hexi tol ring dehydration products, and (2) from 5 to 50 millimoles of at least one hydrocarbon-substituted monohydric phenol of at least 9 carbon atoms having a hydrocarbon substituent in the para-position to 'therhydroxyl group and 0 to 4 additional hydrocarbon substituents in the remainder of the benzene ring, said hydrocarbon substituents being the sole substituents in said phenol and being taken from the group consisting of alkyl, aryl, aral- I kyl and cycloalkyl substituents.

I radical of 1 to '12 carbonatoms. .75

4. An, emulsion as setiorth-in claim 1 wherein said monohydric phenol is 2-benzyl-4-methyl-6-t-butylphenol.

5. An emulsion as set forth in claim 1 wherein said sensitizing agent is the condensation product of ethylene oxide with oleyl alcohol having a molecular weight of at least 300.

6. An emulsion as set forth in claim 1 wherein said sensitizing agent is a polyethylene ether glycol having an average molecular weight of at least 1500.

7. An emulsion as set forth in claim 1 wherein said silver halide is iodobromide.

8. An element as set forth in claim 1 wherein said colloid is gelatin.

9. A photographic element comprising a support hearing at least one layer composed of an emulsion as set forth in claim 1.

18 10. An element as set forth in claim 9 wherein said support is a hydrophobic film base.

11. An element as set forth in claim 9 wherein said support embodies a polyethylene terephthalate film base.

References Cited in the file of this patent UNITED STATES PATENTS 2,341,877 Middleton Feb. 15, 1944 2,441,389 Blake May 11, 1948 2,594,917 Gunther Apr. 29, 1952 2,596,742 Vaughn et al May 13, 1952 2,752,246 Weaver June 26, 1956 2,756,147 Reynolds et a1. July 24, 1956 

1. A PHOTOGRAPHIC, WATER-PERMEABLE COLLOID-SILVER HALIDE EMULSION CONTAINING PER MOLE OF SILVER HALIDE (1) FROM 0.1 TO 2.0 GRAMS OF A NON-OPTICAL SENSITIZING AGENT HAVING A MOLECULAR WEIGHT OF AT LEAST 282 AND CONTAINING AT LEAST 2 OXYALKYLENE UNITS OF 2 TO 4 CARBON ATOMS AND BEING TAKEN FROM THE GROUP CONSISTING OF POLYALKYLENE ETHER GLYCOLS, AND CONDENSATION PRODUCTS OF ALKYLENE OXDIES OF 2 TO 4 CARBON ATOMS WITH MONOHYDRIC ALCOHOLS, GLYCOLS, FATTY ACIDS, SATURATED ALIPHATIC AMINES, AND HEXITOL RING DEHYDRATION PRODUCTS, AND (2) FROM 5 TO 50 MILLIMOLES OF AT LEAST ONE HYDROCARBON-SUBSTITUTED MONOHYDRIC PHENOL OF AT LEAST 9 CARBON ATOMS HAVING A HYDROCARBON SUBSTITUENT IN THE PARA-POSITION TO THE HYDROXYL GROUP AND 0 TO 4 ADDITIONAL HYDROCARBON SUBSTITUENTS IN THE REMAINDER OF THE BENZENE RING, SAID HYDROCARBON SUBSTITUENTS BEING THE SOLE SUBSTITUENTS IN SAID PHENOL AND BEING TAKEN FROM THE GROUP CONSISTING OF ALKYL, ARYL, ARALKYL AND CYCLOALKYL SUBSTITUENTS. 